“How ridiculous and what a stranger he is who is surprised at anything which happens in life.” Marcus Aurelius Meditations Book 12
I think once you fully accept the concept of never being surprised by anything in life, the happier you’ll be. No matter how ridiculous or egregious, it’s probably happened before and it will happen again. This ranges from all kinds rudeness, violence, abuse, lying, etc. Also included are personal tragedies, loss, failures.
Certainly there are things that could pleasantly surprise us as well, but again, these events are part of the rise and fall of life.
Never be surprised.